Supposing that fixation of the love impulse upon the actual person of the parent has been successfully avoided, there remains the possibility of fixation upon the numerous parent substitutes that we considered in Chapter X. These fixations really imply, as we have seen, an incomplete detachment of the erotic impulses from the parental images as they exist in the Unconscious, and should not occur in cases where real freedom from the secret domination of these images has been achieved. Nevertheless we must remember that such freedom is at best only relative; the associative connections that bind the earliest to all subsequent objects of love (either directly or through a series of intermediate links) would seem never to be really broken; in all probability they continue throughout life to exercise a certain measure of influence upon the direction of the affections. All that we can reasonably demand under these circumstances is that these unconscious forces shall not so blind the individual as to cause him to bestow his love upon an object which is intrinsically unsuitable. So long as this is avoided there is little to complain of, and it would seem very probable that a deeper psychological and ethical insight into the nature of the processes concerned will, on the whole, produce a relaxation rather than a further restriction of the liberty that is now permitted in these matters. This at any rate would appear to be the direction in which moral sentiment is moving as culture increases; the maximum of restriction is reached in those communities where, as in parts of Australia, a highly complex system of exogamy allows only a very limited range of choice for the selection of husband or wife; from this point upwards in the scale of development there is a marked tendency for the number of forbidden relationships to become smaller as culture advances, and there is every reason to suppose that in the main this tendency is still at work. Indeed we have only recently witnessed an example of its action in this country in the removal of the ban upon the marriage with a deceased wife's sister. [Sidenote: These tendencies become less repressed and more influenced by reason, as development proceeds]