Fear can be felt mildly, extremely, or somewhere in between. The least intense state of fear is trepidation; this can progressively escalate to nervousness, anxiety, dread, desperation, panic, horror, and terror. The following figure shows a graph of each state of fear and its intensity:

We will now see what each of them represents:

• Trepidation: This involves the anticipation of the possibility of danger. The possible actions resulting from this state are hesitate, ruminate, and worry; the first action is a constructive action, though the last two are destructive actions.
• Nervousness: This involves an uncertainty as to whether there is a danger. The possible actions resulting from this state are hesitate, ruminate, and worry; the first action is a constructive action, though the last two are destructive actions.
• Anxiety: This is a fear of an anticipated or actual threat and uncertainty about one's ability to cope with it. The possible actions resulting from this state are hesitate, freeze, withdraw, ruminate, and worry; the first action is a constructive action. Freeze and withdraw are ambiguous actions and the last two are destructive.
• Dread: This involves an anticipation of severe danger. The possible actions resulting from this state are freeze, withdraw, ruminate, scream/yell, and worry. Freeze, withdraw, and scream are ambiguous actions. Ruminate and worry are destructive
• Desperation: This is a response to the inability to reduce danger. The possible actions resulting from this state are avoid, freeze, hesitate, ruminate, and scream/yell. Ruminate is a destructive action when we feel desperate. All the other actions are ambiguous.
• Panic: This involves sudden uncontrollable fear. The possible actions resulting from this state are freeze, scream/yell, withdraw, ruminate, and worry. The last two actions are destructive. All the others are ambiguous.
• Horror: This involves a mixture of fear, disgust, and shock. The possible actions resulting from this state are: freeze, scream/yell, withdraw - all the actions are ambiguous.
• Terror: This involves an intense overpowering fear. The possible actions resulting from this state are freeze, scream/yell, and withdraw.