The obstacles to consent are all those factors that take away or lessen the voluntariness of an act.

  • Thus, the actual obstacles that affect the intellect are reduced to ignorance, spoken of above; those that affect the will are passion and fear, and that which affects the external powers is coercion.
  • The habitual obstacles are habits and abnormal mental states.


Fear is a disturbance of mind caused by the thought that a future danger is impending. It is an obstacle to consent in various ways:

  • It lessens or takes away freedom of judgment, inasmuch as it hinders or suspends the reasoning processes
  • It lessens the voluntariness of choice, inasmuch as it makes one decide for what is not of itself agreeable.

An act done under fear that impeded the use of judgment is:

  • Involuntary, if the fear was so great that one was temporarily out of one’s mind.

Example: Titus is so panic-stricken at the thought that a wild animal is pursuing him that he fires a revolver in every direction.

  • Less voluntary, if the fear prevents one from thinking with calmness and deliberation.

Example: Caius is being questioned by a stern examiner who demands an immediate reply. Fearing to hesitate, Caius gives what he knows is a “bluffing” answer.

The acts of one who is under fear are of various kinds.

  • Acts are done with fear, when the fear is concomitan, that is, when it is not willed and does not cause the act, but is merely its occasion or would rather prevent it.

Examples: Julius is ordered under pain of death to drink a glass of wine, a thing he was intending to do and which he would have done even without any threats.

Balbus walks along a lonely road, because he must get home, but he trembles at the thought of robbers.

Caius, a highwayman, at the point of the revolver, forces Balbus to hand over his purse, but he fears that the police may arrive before he has secured the money.

Titus, a business man, makes a trip by air, because he must reach another city without delay, but he has some apprehensions about his safety.

All these men act, not because of, but apart from or in spite of their fears.

  • Acts are done through fear, when fear causes an act that would not otherwise be performed.

The fear may be antecedent (i.e., unwilled) or consequent (i.e., willed).

Examples: Balbus, in the case mentioned above, surrendered his purse because of involuntary fear which was caused by the revolver of the robber.

Claudius makes an act of sorrow for sin because of voluntary fear which he produces by thinking of the punishment of hell.

When Fear doesn’t erase liability

The effects of fear, which do not take away the use of reason, on the voluntariness of acts are as follows.

  • Acts done with fear are not made really involuntary on account of the fear that accompanies them, for they are done for their own sake, not out of fear or as a consequence of fear. They may be called relatively involuntary in the sense that, by reason of fear, they are comparatively unpleasant, unless one enjoys the thrill of danger.

Examples: Balbus, Caius and Titus, in the cases mentioned above, acted with perfect willingness. Whether they enjoyed their experiences or not, depends on their attitudes towards adventure and excitement.

Acts done through fear are voluntary simply and absolutely, for the act done under the impulse of fear is what the agent considers here and now as most desirable.

Examples: Balbus’ surrender of his purse and Claudius’ act of contrition are just what these two men wish to do as best suited to the circumstances.

  • Acts done through fear are involuntary in a certain respect, if the agent can retain his inclination towards the opposite of the act and still avoid what he fears; otherwise, they are in no way involuntary.

Examples: Balbus retains his liking for the money taken from him by force, and hence the surrender of it to the highwayman, although voluntary, if all things are considered, is not voluntary, if only the money itself is considered.

Claudius, on the contrary, retains no liking for his sins, for he knows that, if he does, he will defeat the purpose of his act of sorrow, which is to escape the pains of hell; hence, his contrition, although the result of fear, is in no respect involuntary.


Passion is a movement of the sensitive appetite towards its object through love, desire, hope, or its repose therein through delight. It tends towards good, as fear tends away from evil. Passion is an obstacle to consent in the following ways:

  • It takes away voluntariness (i.e., the quality of proceeding from an internal principle with knowledge of the end of the act), whenever it is so intense as to prevent knowledge;
  • It diminishes liberty (i.e., the quality of being perfectly voluntary, or indifferent as between many acts), even when it does not prevent knowledge.
  • Spiritual appetites fortify the reason, but the opposite is true of sensible appetites; for these latter draw all the attention to things that are lower and away from those that are higher, and impede the exercise of imagination and other senses that serve the reason. In extreme and rare cases passion may be so intense as to distract from or prevent altogether the exercise of reason, or to produce insanity. Thus, we sometimes hear of persons losing their minds through affection for money, or of performing irrational deeds under the excitement of joy.

With reference to the will, passion is twofold.

  • It is antecedent, when it precedes the act of the will and causes it. In this case the passion arises not from the will, but from some other cause (e.g., the bodily state, as when a sick man longs for food that is forbidden).

Antecedent passion makes an act more voluntary, since it makes the will tend with greater inclination to its object; but it likewise makes an act less free, since it impedes deliberation and disturbs the power of choice.

Example: A man who takes extreme delight in sports, plays voluntarily, but is less free than if he were not so immoderately inclined that way.

  • Passion is consequent when it follows the act of the will and results from it. This may happen either without the will choosing the passion (as when the very vehemence with which the will desires some object causes a corresponding sensitive emotion to awaken), or because the will has deliberately aroused the emotion in order to be able the better to act through its cooperation.

Consequent passion which results naturally from an intense act of the will does not increase the voluntariness of the act, since it is not its cause; but it does show that the act of the will is intense, for it is only that which is willed vehemently that overflows from the will and affects the emotions.

Consequent passion which results from the deliberate choice of the will increases the voluntariness of the act that follows, since the act is performed with greater intensity on account of the passion that has been deliberately excited.

What has been said about the passions that tend to sensible good can be applied also to the passions that are concerned with sensible evils, such as hatred, sadness, aversion, boldness, anger. If they are antecedent, they increase the voluntariness of an act, but diminish its freedom; and, if they cause a passing frenzy or insanity, they take away all responsibility. If they are consequent, they either increase the willingness of the act, or indicate that it is willed with great intensity.


Violence, or coercion, is the use of force by an external agent to compel one to do what one does not want to do. Its effects on voluntariness are:

  • It cannot affect the internal act of the will, else we should have the contradiction that the act of the will was both voluntary, as proceeding from the will, and involuntary, as proceeding from external coercion.
  • It can affect external acts, such as walking, and so make them involuntary. If a boy is driven to school, the violence makes his going involuntary, but it does not make his will not to go to school involuntary.

TITLE: Christ and the Tree of Life. The Benefits of Reading the Holy Bible and Books of Saints for souls who want to know the Holy Spirit.
AUTHOR: St. Alphonsus Liguori
EDITOR: Pablo Claret

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