The problem with human imagination is really two problems. One is that our imagination is very limited. Thus, for example, I can’t properly imagine the life, or even the schedule, of someone who has two children. The second problem is that we trust our puny imagination a huge deal, enough that we accept its testimony despite perfectly good evidence to the contrary. Thus, for example, an academic with a young child might say things like “they told me that I won’t get any research done the first few months but…. I guess I didn’t take them seriously!”. In other words, he received reliable information but ignored it because his imagination told him he could just get work done when the baby is asleep.
My favorite cases involve not believing a person when she talks about her inner life. Far be it from me to think that people are never wrong about their inner lives, but when a person tells you she thinks or feels or wants something, the simple fact that you can’t imagine thinking or feeling or wanting it is not in itself a reason to doubt her. I once told a relative stranger that though I grew up in a certain country, I do not feel identified with it. The man said “that’s highly unlikely”. I am still a little angry at the person telling me what I feel, but I don’t have the right to feel superior to him. After all, for decades, I believed that any person who claims to be “full” after a salad – a mere salad! – is either lying to me or lying to herself. To my defense, there exist some people who confess that they have kidded themselves on this particular topic, but I admit that the main reason I failed to believe people who claim to be full after a salad is that I can’t properly imagine being full from eating (only) a salad. That’s a bad reason.