I think that the reason we hate is because we FIRST loved. An example would be that Americans hate terrorists because they love their country. A man hates the other man that sleeps with his wife, because he loves his wife. Does this idea have any relevance in modern philosophy, or has it already been covered? I'm not very versed with philosophical writings.

Your examples are good ones. Still, I doubt that hatred always presupposes love in the way you suggest. Consider a girl born into slavery, separated from her mother at birth, and abused by her owner. She may come to hate this man, it would seem, even if she never loved -- never really had a chance to love -- anyone or anything.

You may respond that she hates the man, and the abuse he inflicts upon her, only because she longs for, and loves, living unabused.

As an empirical claim about human psychology, this is dubious. The little girl may not have enough of a conception of what life without abuse would be like to be said to love such a life.

To get around such worries, in this and all other cases, someone might say that it is part of the meaning of hating that one loves some enemy or opposite of what one hates. In this way you can win your case by showing that every proposition of the form "A hates X" presupposes a proposition of the form "A loves Y (e.g., not-X)".

But if we take this step, we are left with just a dull conceptual point that tells us something about how we relate the meanings of two words and nothing about human psychology.

It's not conceptual insights about the meanings of "love" and "hate" that you are after, I think, but empirical insights about the role of love and hatred in human psychology. This is a field very much worthy of further study. But the insights you'll find there are likely to be more complicated than the very general hypothesis you've offered.

While we are thinking about the relationship between love and hate, what about love-love and hate-hate? Would X hate Y just because Y hates X? And so forth. Here's a version of something I cover in my introduction to philosophy course. Consider the psychological hypothesis that in order for a person to be able to love another person, he or she must already have been loved by someone else (earlier). For example, parents must love their children if their children are to be able to love other persons later. But how were the parents able to love their children? By our hypothesis, by being loved by someone else, say, their parents. But why were they able to love? We have a causal stream paradox. Perhaps at one point, way back, there was someone who was able to love in the absence of himself or herself being loved. This original unloved lover started things going. But then our hypothesis is false. Or perhaps God loved that person, who was not loved by any other person, in which case we can get the stream of love going without violating our hypothesis. But now we have to say that God, at least, can love without being loved. But if God loved that humanly-unloved person in order that this person would be able to love other persons and get the love-stream going, then there is no reason to assert our hypothesis. For any humanly-unloved person today will be able to love others as long as God loves him or her. Given the characterization of God as all-loving, we are all loved by God and hence will be able to love others in spite of the fact that we are not loved by other humans. Perhaps we should assert only that, ceteris paribus, a person is less likely to be able to love others if he or she has not been loved by others. This more reasonable claim might be true, but might also be a truism. Without a precise statement of the other conditions that are necessary and of the relationship between these and the loving-beloved chain, the psychology of love becomes a guessing game. (Is there a hate stream? Hate generates more hate....)

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