First, how should the SPs be defined? A straightforward one should be like “parts of personality holding anger or destructiveness.” It also has a connotation of shadowy figures behind the scence who pull strings. Another important nature is its relative anonymity. They are often referred to as “it”, “unknown” or “anonymous”. They sometimes have an implication that they are not supposed to be born or are not worthy of existing in this world. Its appearance is typically ephemeral, passing and without demonstrating any attempt of contacting other personalities or people outside. To put these characteristic together, SPs should be formulated more in detail; “Parts of personalities which hold anger and destructiveness, which tend not to be identified, and appear only temporarily in a rather critical occasions.”
This definition includes three components in SPs: anger/aggression, unidentifiability, passing appearence in critical situations. I will elaborate rather in detail on these three components rather in detail.
Anger/aggressiveness
It is often unclear who a SP is mad at when it exhibits anger and frustration. When a SP shows anger, it tends to direct it in a rather indiscriminate way. It might yell at, or lunge toward whoever is around. It might attack whoever seems to incriminate the host personality, obviously in his/her protection. However, it might hurt the body of the host, or even try to kill him/her, which eventually kill itself. Some SP, when asked why he engages in self-destructive behaviors that simultaneously endanger SP itself, states, "I don't really care. I'm totally OK if I die. Or I don't even know if I'm alive or not".
Difficulty being identified
One of the reasons why SPs sometimes do not seem to own their clear identification is because they are not fully formed as a personality; they are not altogether crystallized in their character formation. Often they are in a trans-like state or somnambulism, in a clouded consciousness, without a capacity to identify him/herself or even respond to a question. When a SP is in a fugue state, they would wonder without purpose or destination. However, there are other cases where SPs simply do not want to be seen or identified. Some SP send its clinician a blunt message, such as "leave her alone" or " don't mess with us", or "don't even try to get hold of me", expressing their deep distrust and clear wish to alienate the clinician.
報酬系23
このように考えると、この動的快＝合目的的行動は生命体の生存を欠けた活動に決定的な役割を担っていることがわかる。動物がやっていることは、ことごとくこれではないか？働き蜂が一心に蜂の巣を作っていく。アリたちが一糸乱れずえさを運んで行く。彼らは強烈で頑強な動因に支えられているようである。もちろん皆さんは言うだろう。「彼らは本能でやっているのでしょう？いわばロボットのようなものでそこに意志とかモティベーションを考えるのはおかしいのではないでしょうか？」もちろんこの反論はよくわかる。確かに働きアリは一種のロボットのようなものであろう。しかし進化をたどれば確実に同じような行動を、脊椎動物や哺乳類にも見出すことが出来る。特に生殖にまつわる行動はまさにそうではないか。一心不乱に川上を目指す鮭の例はすでに出してある。おそらくその構造は先ほど述べた叱咤激励型であろう。生物学的に見て、痛み回避の仕組みははるかに単純で原始的であろう。はりでつつくと身を避けるアメーバのように。しかし「激励」は「報酬勾配」が設けられる必要上複雑である。するとこの叱咤と激励、鞭と人参のバランスが決め手だろうか？ここで叱咤とともに激励が重要と考えられるのは、生殖においては、目的がかなり定まっているからだ。相手の生殖器に自分の生殖器を接合させるという芸当は、痛み刺激から遠ざかるよりもはるかに繊細な動きを必要とするのである。私は疑問なのだが、どうして昆虫レベルで交接が可能なのかが今一つ実感がない。こちらのターゲットもあちらのターゲットも極めて限られているのに、それを接合させる生命の力は驚くべきものである。
