4 min read

The weighing problem

One of the most important attitudes in critical thinking is remaining imaginative. You have to keep looking for alternatives, whether they are alternative explanations, alternative forecasts, alternative plans of action or alternative solutions to a problem. Keeping our minds open to alternatives helps us to stay clear of a number of cognitive biases, from confirmation bias to sunk cost fallacy.

Yet doing so in practice is really hard, even in those cases when the alternative options themselves come easily. For one, the quest for alternatives leads to a halting problem. Since you never know whether you have exhausted all important options, you can never be sure whether you should stop looking for new ones. Secondly, once you have decided to stop dreaming up new ideas, there is a weighing problem: it is often not immediately obvious how to pit the pros and cons of different options against each other.

There are systematic ways of dealing with these problems, but those are time-intensive and sometimes it makes more sense to use quick-and-dirty approaches. For the halting problem, doing so is easy: just commit yourself to a specific number of options or to a preset amount of time you are willing to spend on seeking out alternatives. The weighing problem, however, is by definition a deliberative problem. Even when cutting corners, you will have to employ careful thinking when comparing options. Right?

The power of unconscious judgment

A series of experiments from the 2000s cast doubt on that intuition. Ap Dijksterhuis and colleagues had participants make complicated consumer choices. Some of them had the time to consciously deliberate about their decision, others were given no such time at all and again others were given the time, but not the attentional resources needed to make their choice. In the end, the latter group tended to do well: people who make complicated decisions unconsciously, Dijksterhuis argued, also have better outcomes. Applied to critical thinking, this would mean that identifying options and then not consciously deliberating on them would not just be a quick-and-dirty solution to the weighing problem, but would be the optimal way of going about!

In the theory built around Dijksterhuis’ findings, conscious thought has too narrow a bandwith to deal with complex issues. For him, conscious thought is a tool for simple decisions. As soon as you have to compare options with a high amount of attributes, it’s unconscious processing you need (Dijksterhuis & Nordgren, 2006). Indeed, once asked to reflect on their choice, unconscious choosers tend to state they decided holistically (for whatever that’s worth, given that they decided unconsciously), while conscious choosers claim to have focused on a small selection of attributes.

Yet from a critical thinking perspective, there is something odd about Dijksterhuis’ claim. Once we compare alternatives unconsciously and base our choices on gut feeling, it becomes very difficult to learn from outcomes. Does a bad outcome mean the underlying reasoning was poor? If so, which part of the reasoning was poor? There’s a lot at stake here: if examining our reasoning in order to improve it turns out to be a futile task, the majority of critical thinking trainings can be thrown out of the window.

Thinking longer about unconscious thinking

The findings of Dijksterhuis have since been criticized on methodological grounds (Newell & Shanks, 2014). Replication proved difficult and the superiority of unconscious decision-making was mostly apparent in studies with small subject sizes. Moreover, additional experiments suggested that it was not unconscious cognition that improved decision-making, but rather the artificial, extended deliberation period in the early experiments that had hampered decision-making. The idea behind this reasoning is that being forced to think long about a decision lowers its quality, as information with hardly any relevance gets attended anyway and degrades initial judgment. Indeed, a set-up in which participants could self-pace their conscious deliberation showed no difference with unconscious decision-making, but both conditions worked better than artificially extended conscious deliberation (Payne et al., 2008).

Additionally, experiments employing choice scenarios that drew on expertise — such as medical doctors making diagnoses — painted a wholly different picture than the consumer choice decision-making of Dijksterhuis did . In such cases, deliberation improved the decision-making of specialists in comparison to a distracted condition (Mamede et al., 2010). This suggests that if you have the mental schemes and experience to make use of a long deliberation time, you can benefit from doing so.

Quick-and-dirty deliberation

It appears then, that the case for tuning out to let your unconscious mind do the heavy lifting is not very strong. That’s not to say that weighing options should always involve lengthy deliberation – in fact, some of the work cited above suggests that quick thinking can be better than drawn out analysis. That’s good news if you want to take a critical look at options but don’t want to spend much time doing so.

In such cases, a good trick may be to reduce the complexity of your comparison. For example, you can pick one of your options (say, the status quo) and list three strengths and one weakness of this option, ranked by importance. Then, you seek out an alternative option that addresses the weakness of the first option. Does this new option threaten one or more strengths of the first option? If not, it might just be a better option than the status quo. If so, then the question is whether getting rid of the weakness of your first option is worth the (partial) sacrifice of its strengths.

This quick-and-dirty form of deliberation saves you from ranking and comparing all relevant attributes, which is a time-consuming process. It also allows you to zoom into options that have promise, because they address a salient weakness. Reducing complexity does make you susceptible to biases when choosing which attributes are relevant, however. This becomes especially problematic if you are not making a consumer-type decision but are, for example, weighing evidence for and against a statement. When tunnel vision and confirmation bias are likely, quick-and-dirty approaches just don’t work out – you will need to deliberate systematically and deeply.


Dijksterhuis, A., & Nordgren, L. F. (2006). A theory of unconscious thought. Perspectives on Psychological science1(2), 95-109.

Mamede, S., Schmidt, H. G., Rikers, R. M., Custers, E. J., Splinter, T. A., & van Saase, J. L. (2010). Conscious thought beats deliberation without attention in diagnostic decision-making: at least when you are an expert. Psychological research74(6), 586-592.

Newell, B. R., & Shanks, D. R. (2014). Unconscious influences on decision making: A critical review. Behavioral and brain sciences37(1), 1-19.

Payne, J. W., Samper, A., Bettman, J. R., & Luce, M. F. (2008). Boundary conditions on unconscious thought in complex decision making. Psychological Science19(11), 1118-1123.