Okay, so maybe we could kind of break these needs into broad categories in order to talk about them in relation to sex. So for example, there's biological, there's psychological, there's sort of more that social or interactional category. And then even for some people, like, that spiritual category of need. Right? >> Yeah. I'm not sure we can be calling them categories. >> Okay. >> We can obviously be thinking of them as conceptual categories. >> Mm-hm. >> But I think in real life, they do overlap. >> Right. >> And interact with each other. So we can actually start with the biological. >> Mm-hm. >> When we think biological, we think of like a natural drive and people would be driven to have sex and sometimes for procreational purpose. But I would say that now in most places, the procreational purpose is probably not the central motivation for sex. It still is I think in some context. I would say a majority of people likely, they are sort of driven to achieve a certain kind of physical pleasure. And sexual pleasure is actually not easy to describe in any kind of comprehensive exhaustive way because when people experience sexual pleasure, it can be like just a kind of pleasurable sexual stimulation. And like earlier generations of sex researchers like Masters and Johnson have developed sort of a very schematic description of the process which may or may not apply to everyone. But I think it's like physical pleasure is a key part, but then like the kind of physical pleasure that is experienced by people is also, I think, not always standard. And there are a lot of variations I must say, in the way that people experience physical pleasure associated with sex. Some people, for example, locate sexual pleasure in specific parts of their body. Some people have sort of a more diffused experience of that pleasure in terms of where it is in the body. And then, some people are sort of more focused on the physical sensation. Some people tend to ascribe more significance to the emotional meaning, the feeling of intimacy. Or some people experience a sense of security when they're interacting with people physically. But some people are not comfortable at all with sexual arousal and even sexual feelings within their own body. So, we have a wide variety of responses among individuals.