Complex sentence: If egoism suggests that an individual seeks his own ends without regard to the interests of or consequences to others in differs from individualism which may be simplified as minding one's own business and letting others mind theirs.
Split into simpler sentences: If egoism suggests that an individual seeks his own ends without regard to the interests of or consequences to others, it differs from individualism. Individualism may be simplified as minding one's own business and letting others mind theirs.