Persuasion
Convince
noun, verbal noun
You acquire theory after theory. In doing this, you have a lot of theories in your head. You use all these theories as tools for persuasion. These theories will allow you to convince anyone of anything.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well. The 説 gets shortened to せっ.
これ以上説得のよ地は無いよ。
There is no room for persuasion anymore.
コウイチを説得するのは岩を手でわるのよりもむずかしいと言われています。
They say it would be harder to persuade Koichi of something than it would be to break a rock with your hand.
日本に住むために、まず最初に自分の親を説得しなくてはいけません。
In order to live in Japan, the first thing I have to do is convince my parents to let me do it.