Sri Aurobindo
Letters of Sri Aurobindo
Volume II - Part 3
Perception is not enough to transform the nature. Paśyataḥ1 in the spiritual language does not mean only perception. Perception is of the mind and a mental perception is not enough – a substantial and dynamic realisation in all the being is necessary. Otherwise one of three things may happen. (1) The mind perceives oneness but the vital is not affected, it goes on with its impulses, for the vital is governed not by thought or reason but by tendency, impulse, desire-force – it uses reason only as a justification for its tendencies. Or even the vital may say, “All is one so it does not matter what I do. Why should not I seek oneness with others in my own way?” (2) If the mind has a realisation, but the vital does not share in it or distorts it, then also the vital can insist on its own way or even carry the mind 
along with it. As the Gita says, the senses (vital) carry away the mind even of the sage who sees, as the wind carries away a ship on a stormy sea. (3) The inner being may have the realisation strongly and live in the oneness, calm, peace, but the interior parts of the outer may feel the reactions of desire etc. In this case the reactions are more superficial; but even so rejection is needed till they cease. When all the being lives in the solid realisation of calm, peace, liberation, oneness, then the desires fall away and the necessity of rejection ceases, because there is nothing to reject any longer.