Hope, Scientifically Speaking

By Tyler VanderWeele

Tyler VanderWeele is the Director of the Human Flourishing Program, which was founded in 2016 at Harvard’s Institute for Quantitative Social Science. The Human Flourishing Program aims to study and promote human flourishing and to develop systematic approaches to the synthesis of knowledge across disciplines. This research update (below) is published with the permission of the author to give our readers an idea about current empirical research on the virtue of hope, about efforts at developing more philosophically and theologically informed measures of hope and of optimism, and about the possibilities of hope for the future. In Dr. VanderWeele’s words:

Hope… for the Next Year, and Beyond

This past year has been difficult for our country, and for the world. We have been struggling through a deadly pandemic. We have faced tensions across racial and political lines. Many have faced tremendous economic hardship. Some are doubtless wondering if there is any reason for hope. Dare we hope for the future? And what is hope? Is it realistic? Does it help at all? Over the past couple of years, we have been trying to better understand and assess hope at the Human Flourishing Program at Harvard, to attempt to shed light on some of these critical questions of our day.

The Nature of Hope

A recent report from the John Templeton Foundation on hope and optimism, authored by philosopher Michael Milona, provides a helpful summary of some of the important empirical, philosophical, and theological insights into hope. Hope differs from optimism in not necessarily presuming or expecting that the future will be good, but focusing on the possibility that it will be good nonetheless. Hope entails a desire for something good in the future, and a belief that this is possible. But hope is more than just belief and desire. Thomas Aquinas proposed that hope is a desire for some good that arises out of the perception that this future good is difficult, but not impossible, to obtain. In Michael Milona’s account, hope extends beyond belief and desire to include a reason for action to try to obtain the future good. Hope fixes one’s attention on the possibility that the future will be good, and empowers one to act, or to wait, to receive that good, even in the midst of difficulties and uncertainty.

Milona discusses how it may sometimes seem that there are dangers in hoping, such as complacency, or an unrealistic set of expectations, or an otherworldliness that may not be conducive to appropriate action, or to flourishing. However, he also notes that hope need not necessarily result in such things. One can have a realistic assessment of the situation, and of the difficulties and uncertainties, and yet still hope. And such hope can sometimes be the motivation for action. Nevertheless, given these potential objections, we might reasonably wonder whether hope really contributes to human well-being. This is a question we have been examining empirically at the Human Flourishing Program.

Our Study and the Effects of Hope

We have recently published a paper on the effects of hope on health and well-being. This study used data from about 13,000 older adult participants in the Health and Retirement Study, and employed methodology similar to our recent paper on volunteering. We used longitudinal data, which ensures that a prospective cause actually precedes its potential effects, and analyzed the effect of hope on a wide range of outcomes (which also reduces the dangers of selective reporting and publication bias). We further controlled for baseline levels of hope and baseline levels of outcomes, along with a rich set of demographic, physical, and psychological factors, and used “sensitivity analysis” to assess how robust the associations we identified were to unmeasured confounding. These approaches allow us to at least provide evidence about potential causal effects of hope on many aspects of wellbeing. 

What we found was that having high levels of hope led to slightly decreased (16% lower) mortality risk during the 4 years of follow-up, as well as fewer subsequent chronic health conditions; it also led to lower levels of depression, negative affect, and loneliness; notably higher life satisfaction, happiness, purpose in life, and sense of mastery; and perhaps somewhat greater physical activity. We did not, however, find evidence for an effect on all outcomes. Interestingly, we found little or no evidence for an association of hope with reduced subsequent smoking or binge drinking, and no evidence for effects on conditions such as diabetes, hypertension, or arthritis. Even the important associations with subsequently lower 4-year mortality risk are smaller than analogous associations for volunteering or for religious service attendance.

However, our study did not uncover any detrimental effects of hope and it did provide evidence that it has important effects on many health and well-being outcomes. The evidence from our study, looking at many different outcomes, certainly does suggest that the effects of hope, at least on average, are notably beneficial.

Measurement of Hope and Optimism

This study (of the effects of hope on health and well-being) was not without its limitations, particularly related to challenges in measuring hope. The measure of hope we used in the Health and Retirement Study in fact employed a series of statements about hopelessness; the study assessed participants’ hopefulness by the extent to which they rejected these statements. But might we measure hope in a more satisfactory way?

The dominant model for hope measurement in much psychological research is Charles Snyder’s approach of assessing a person’s sense of pathways to a desired outcome, and of agency to make use of those pathways. But this approach has been criticized (including in Milona’s report) for failing to capture hope as most people seem to understand it, and of missing the possibility of hoping against the odds. As noted above, hope does not necessarily entail expectation of the

desired outcome, and hope characteristically is operative in the face of difficulties. Items in Snyder’s scale such as “I’ve been pretty successful in life” do not seem to capture hope at all.

In his report, Michael Milona expressed the need for more philosophically grounded measures of hope for empirical research. Recognizing this need, for the past two years we at the Human Flourishing Program have been working to develop more conceptually adequate measures of hope and optimism, in collaboration with several of our colleagues at Harvard’s Center for Happiness and Health, along with philosopher Nancy Snow at the University of Oklahoma, and theologian Edward Brooks at the University of Oxford. Our items and questions concerning hope are grounded in Aquinas’ conception of hope as pertaining to a difficult but possible future good, while our items concerning optimism distinguish between “groundless optimism” in which the expectation of future good is without any reasonable basis and is thus irrational (a criticism of optimism often rightly raised by philosophers) from “grounded” optimism that might be based on one’s resources or one’s willingness to exert effort.

In this work, we’ve both been trying to develop better measures, and also to better distinguish hope from optimism, with the aim of better understanding the effects of hope and optimism on human well-being. We have begun some cognitive testing and data collection on the hope items, but if any of our readers are interested in assisting with more substantial data collection efforts on our hope or optimism measures (or both), please feel free to contact us. We will be releasing these publicly once we have better information on their performance in cognitive testing and on their psychometric properties.

Hope for the New Year, and Beyond

But research is one thing. Realistically confronting the world we live in today is another. Can we truly hope today? As COVID case-rates soar and much of our social fabric seems to be fraying, despair might seem the most reasonable response. The vaccine trials appear to be promising, but this is occurring in the midst of daily COVID mortality reaching all-time highs. Efforts are needed to bring this pandemic to an end and to restore life. We need hope; we need to focus on the future difficult but possible good; we need reasons for action amidst the challenges.

We will also need rebuilding and reinforcing of society and civilization and of those areas of social and cultural life that have deteriorated, declined, or been destroyed. We need hope. We should, moreover, also clarify what our hopes are, and what we truly value. The pandemic has often led to a conflict of numerous competing values and ends. We need clarity on what matters most. We need to see clearly what we, as individuals, and as a society, value, and what we hope for. What is it that we want, and hope, for our world?

During this upcoming holiday and Christmas season, those within the Christian tradition also remember a deeper and more longstanding hope, a hope mysteriously grounded in the birth of Jesus Christ, and all that followed from his life. It is a hope for a more final and powerful restoration to the good. Properly understood, it is not a hope that deters one from acting here and now, but one that gives reasons for such action – so as to bring about a better world. It is a hope that is made manifest, with its end ultimately attained, in love – a love of neighbor and love of God – a love that we are to show one another.


With our gratitude to Tyler VanderWeele, Director, Human Flourishing Program, Harvard University. The Human Flourishing Program at Harvard’s Institute for Quantitative Social Science aims to study and promote human flourishing, and to develop systematic approaches to the synthesis of knowledge across disciplines. You can sign up here for a monthly research e-mail from the Human Flourishing Program, or click here to follow us on Twitter. For past postings please see our Psychology Today Human Flourishing Blog. A permanent link to this research note is available here.
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