It would have been better for man had he not been created, but now that he has been created, he must carefully examine his actions.(Eruvin 13b).
Some people have made themselves modern disciples of Epicurus. After noting the prevalence of suffering and distress in the world, they conclude that humans are innocent victims of unjustified misery. Therefore, they find no reason to further restrict the few pleasures that people can have, and they say, "Let people do whatever their hearts desire."
These people act as though they were the first to discover the plight of mankind. The above Talmudic passage should teach them that several thousand years ago, some very wise people had already thoroughly analyzed human life. Although they too concluded that it would have been better for humanity not to have been created, we still do not have carte blanche to do whatever we please.
Our emotions profoundly influence our thought processes. People may come to conclusions that are completely false, but they will believe them to be correct because they want to believe them. This fallacy is dangerous; if someone indulges himself and knows that he is doing wrong, there is a possibility of teshuvah, but if he deceives himself and believes that he is just in his behavior, there is no possibility of teshuvah.
Try an experiment. Take an opinion you have about any issue. Now, consult the works of Torah literature. You will find, without exception, that every issue you raise has been thoroughly discussed centuries ago.